The goal of this set of analyses is to take a deeper dive into the 2019 Seattle calls for service data. To follow up on the preliminary exploratory analysis, we will focus on three types of cases - Disturbance, Suspicious person, and trespass - as well as one type of case resolution - No possible action possible. The questions we want to address here include the following:

  1. Where did the three types of cases occur?
  2. How were these three types of cases resolved?
  3. Does the type of resolution differ by location?
  4. What types of cases were cleared without police action?
  5. Where are the cases that were resolved without police action located?

Focal Case Types

Where are these 3 types of cases occuring?

Table 1: Frequency of Focal Case Types
Case Type # of Calls
Disturbance 92,398
Suspicious Person 48,878
Trespass 24,500 
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Table 1: Frequency of Focal Case Types
Case Type # of Calls Calls per Sq. Mile
Disturbance 92,398 974.50
Suspicious Person 48,878 515.51
Trespass 24,500 258.40
All 3 Focal Cases 165,776 1,748.41

Even when we limit our focus to disturbance, trespass, and suspicious person cases, the north and west precincts lead in the number calls. Table 2 indicates that the north and west precincts together had just under 60% of all calls for the three types of cases. Further, the north had just about double the number of calls for these types of cases than the south precinct.

Table 2: Calls By Precinct for all 3 Case Types
Precinct # Calls %
NORTH 50,612 30.53
WEST 46,365 27.97
EAST 26,527 16.00
SOUTH 24,735 14.92
SOUTHWEST 17,514 10.57

The bar graph below (Figure 1) breaks down the types of cases within each precinct. Below figure 1, Table 3 presents the frequencies for each case type and precinct.

Disturbances are the majority of cases in all precincts. Although over 50% of the focal cases are disturbance in all five precincts, the northern precinct had about 4 to 5 percentage point fewer disturbance cases than the other four precincts. This seems to be driven by the fact that the northern precinct had a sizable amount of suspicious person cases - 35.5%.

The north and southwest precincts lead in the share of suspicious persons. Just over one-third of the calls in these two precincts are about suspicious persons. In fact, in the southwest precinct, there were only 4,000 fewer calls about suspicious persons than disturbances.

The western precinct has the highest number and share of trespass calls. 22% of all calls in the western precinct were reports of trespassing. Notice that in the western precinct the trespass and suspicious person calls have very similar percentages. No other precincts had two case types that were equally distributed. Lastly, the number of calls about trespassing in the western precinct - 10,216 - doubled the number of calls in each of the other precincts.

Table 3: Calls By Precinct & Case Type
Case Precinct # Calls % in Precinct
Disturbance SOUTH 14,334 57.95
Disturbance SOUTHWEST 10,041 57.33
Disturbance EAST 15,185 57.24
Disturbance WEST 26,186 56.48
Disturbance NORTH 26,649 52.65
Suspicious Person SOUTHWEST 6,346 36.23
Suspicious Person NORTH 17,990 35.54
Suspicious Person SOUTH 7,639 30.88
Suspicious Person EAST 6,920 26.09
Suspicious Person WEST 9,963 21.49
Trespass WEST 10,216 22.03
Trespass EAST 4,422 16.67
Trespass NORTH 5,973 11.80
Trespass SOUTH 2,762 11.17
Trespass SOUTHWEST 1,127 6.43

Precinct-Sector Level Case Distribution

Table: Calls By Precinct & Case Type
Case Precinct Sector # Calls % in Precinct
Disturbance SOUTH SAM 5,382 68.0
Disturbance WEST DAVID 6,746 60.4
Disturbance SOUTHWEST WILLIAM 5,103 59.3
Disturbance EAST EDWARD 7,413 58.0
Disturbance EAST GEORGE 3,980 57.2
Disturbance WEST KING 9,008 57.0
Disturbance EAST CHARLIE 3,792 55.8
Disturbance SOUTHWEST FRANK 4,931 55.4
Disturbance NORTH UNION 6,600 55.3
Disturbance SOUTH ROBERT 5,498 54.8
Disturbance WEST QUEEN 4,901 54.5
Disturbance NORTH LINCOLN 5,282 54.4
Disturbance NORTH NORA 5,538 54.4
Disturbance WEST MARY 5,531 53.3
Disturbance NORTH BOY 5,850 51.1
Disturbance SOUTH OCEAN 3,451 50.8
Disturbance NORTH JOHN 3,379 46.0
Suspicious Person NORTH JOHN 3,098 42.1
Suspicious Person NORTH BOY 4,364 38.1
Suspicious Person SOUTHWEST FRANK 3,350 37.6
Suspicious Person SOUTHWEST WILLIAM 2,987 34.7
Suspicious Person NORTH UNION 4,075 34.1
Suspicious Person SOUTH OCEAN 2,265 33.4
Suspicious Person SOUTH ROBERT 3,344 33.3
Suspicious Person NORTH NORA 3,367 33.1
Suspicious Person NORTH LINCOLN 3,086 31.8
Suspicious Person EAST CHARLIE 2,009 29.6
Suspicious Person WEST QUEEN 2,632 29.2
Suspicious Person EAST GEORGE 1,903 27.3
Suspicious Person SOUTH SAM 2,025 25.6
Suspicious Person WEST DAVID 2,691 24.1
Suspicious Person EAST EDWARD 3,008 23.6
Suspicious Person WEST MARY 2,021 19.5
Suspicious Person WEST KING 2,619 16.6
Trespass WEST MARY 2,827 27.2
Trespass WEST KING 4,184 26.5
Trespass EAST EDWARD 2,350 18.4
Trespass WEST QUEEN 1,467 16.3
Trespass SOUTH OCEAN 1,071 15.8
Trespass WEST DAVID 1,738 15.6
Trespass EAST GEORGE 1,077 15.5
Trespass EAST CHARLIE 995 14.6
Trespass NORTH LINCOLN 1,337 13.8
Trespass NORTH NORA 1,268 12.5
Trespass NORTH JOHN 874 11.9
Trespass SOUTH ROBERT 1,186 11.8
Trespass NORTH BOY 1,230 10.7
Trespass NORTH UNION 1,264 10.6
Trespass SOUTHWEST FRANK 617 6.9
Trespass SOUTH SAM 505 6.4
Trespass SOUTHWEST WILLIAM 510 5.9
Table: Resolution by Precinct
Precinct Case Type # Calls % in Precinct
SOUTH Disturbance 14,334 57.95
SOUTH Suspicious Person 7,639 30.88
SOUTH Trespass 2,762 11.17
EAST Disturbance 15,185 57.24
EAST Suspicious Person 6,920 26.09
EAST Trespass 4,422 16.67
SOUTHWEST Disturbance 10,041 57.33
SOUTHWEST Suspicious Person 6,346 36.23
SOUTHWEST Trespass 1,127 6.43
WEST Disturbance 26,186 56.48
WEST Suspicious Person 9,963 21.49
WEST Trespass 10,216 22.03
NORTH Disturbance 26,649 52.65
NORTH Suspicious Person 17,990 35.54
NORTH Trespass 5,973 11.80

Resolutions by Case Type

Assistance rendered is the most common type of resolution for each of the three case types. Report written with no arrest is the next most common resolution for disturbance and trespass cases, and the third for suspicious person. Another common resolution was not being able to locate the incident/complainant, ranking third most common for disturbances, second in suspicious person cases, and fifth in trespass cases.

No police action deemed possible or necessary was fourth most common resolution for disturbance and suspicious persons cases. For trespass cases, no police action deemed possible or necessary was the sixth most common resolution with fewer than 1,000 cases.

There were some top-five resolutions that were unique to certain case types. For disturbances, responding units being canceled by the radio rounded out the top five types of resolutions. The ranking of resolutions for suspicious persons cases looked similar to disturbances. However, the suspicious persons top five was rounded out here with a written street check, though the total calls is noticeably lower than the no-police action necessary or possible resolution. The rankings for trespass cases differed from the other two types. For trespass cases, physical arrests and oral warnings were the third and fourth most common resolutions. Still, the number of trespass cases resolved with arrests and oral warnings are about one-quarter and one-tenth the number resolved by police rendering assistance.

Let’s focus on the top-5 resolutions for these cases of interest (as well as the (and no police action deemed necessary or possible for trespass, which falls just outside of the top 5). In the map series below we start to map these out.

Cases where no police action was possible or necessary

No police action was deemed possible or necessary for 19,290 calls. There are 63 types of cases that had been deemed impossible or unnecessary for police action to be taken. In the graph below, the number of calls for each of the top 20 case types with the no police action resolution are shown. You can see disturbance and suspicious person are the top 2 most common. Disturbance calls make up about 27% of these cases and suspicious person cases are 15%. Trespass cases are in the top 20, but rank lower than our other two focal cases at 9th most frequent.

Other Thoughts:

  • Suspicious circumstances - The frequencies seem to closely track with suspicious person cases. Perhaps run comparisons between suspicious persons and circumstances spatially.
  • Prowler - Trespass and prowler also tend to mirror each other in tabulations. Tracking these two spatially may be useful too.

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The precinct-level map shows that the cases resolved without police action are largely in the north and west precincts.

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Kernel Density

Getis- Ord GI static Map

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Interactive Map of Getis-Ord GI Hot Spots

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